1. Implying that to know whether or not one's driving is impaired while drunk one has to have drunk-driven? 2. Have you even done the research yourself? Clearly you've not so I'll do it for you. http://adai.uw.edu/marijuana/factsheets/driving.htm http://www.washingtonpost.com/cars/pot-smoking-could-affect-driving-for-weeks-researchers-suggest/2013/03/05/1e10733e-85c5-11e2-a80b-3edc779b676f_story.html 3. Marijuana, definitively speaking and objectively so, impairs your reaction time, hand-eye coordination, and short-term memory, all of which are necessary for driving. 4. I'm not against pot in general; I'm for its legalization. I just don't think some potheads should get to drive high and endanger others because they swear they're fine. It's the same exact argument that people give for driving drunk. "No I swear I'm fine." "I never get in an accident when I'm drunk." "I think driving drunk actually makes me a little better." It's all bullshit.